Nozzle and gas diffuser assemblies for welding torches

ABSTRACT

A nozzle assembly for a welding torch is disclosed. The nozzle assembly comprises a nozzle, a contact tip, and a gas diffuser assembly. The gas diffuser assembly comprises a gas diffuser, coupled to an insulator. The gas diffuser is also coupled to a gooseneck and the contact tip. The nozzle is coupled to the gas diffuser assembly, such that the contact tip is retained within the nozzle. The nozzle and gas diffuser assembly further include complementary engagement features to couple the nozzle to the gas diffuser assembly. The nozzle also includes a spatter deflector configured to deflect or block spatter from obstructing gas holes of the gas diffuser assembly.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional PatentApplication Ser. No. 62/439,831 filed Dec. 28, 2016, entitled “WELDINGTORCHES, DIFFUSERS, INSULATORS, NOZZLES, AND CONTACT TIPS.” The entirecontents of U.S. Provisional Patent Application Ser. No. 62/439,831 areexpressly incorporated herein by reference.

BACKGROUND

This disclosure generally relates to welding and, more particularly, tonozzles and gas diffuser assemblies for welding torches.

Conventional welding torches may suffer from one or more of thefollowing issues: inadequate spatter resistance, inadequate access towelding components affected by spatter, inadequate nozzle durability,difficulty of use (particularly by low-skilled welders), and/orsusceptibility to burn backs.

BRIEF SUMMARY

Systems and methods are provided for welding torches, diffusers,insulators, nozzles, and contact tips, substantially as shown in and/ordescribed in connection with at least one of the figures, as set forthmore completely in the claims.

These and other advantages, aspects and novel features of the presentinvention, as well as details of an illustrated example thereof, will bemore fully understood from the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating an example welding system, inaccordance with aspects of this disclosure.

FIG. 2 is a side view of an example welding torch, in accordance withaspects of this disclosure.

FIG. 3a is an exploded side view of an example nozzle assembly, inaccordance with aspects of this disclosure.

FIG. 3b is an exploded side cross section view of the example nozzleassembly shown in FIG. 3a along line 3 b-3 b.

FIG. 4 is an exploded perspective view of an example gas diffuserassembly, in accordance with aspects of this disclosure.

FIG. 5a is a perspective view of an example gas diffuser, in accordancewith aspects of this disclosure.

FIG. 5b is a perspective view of another example gas diffuser, inaccordance with aspects of this disclosure.

FIG. 5c is a side view of the example gas diffuser shown in FIG. 5 a.

FIG. 5d is a side cross section view of the example gas diffuser shownin FIG. 5c , along line 5 c-5 c.

FIG. 6a is a perspective view of an example diffuser insert, inaccordance with aspects of this disclosure.

FIG. 6b is a side view of the example diffuser insert shown in FIG. 6 a.

FIG. 6c is a front view of the example diffuser insert shown in FIG. 6a.

FIG. 6d is a side cross section view of the example diffuser insertshown in FIG. 6c , along line 6 d-6 d.

FIG. 7a is a perspective view of an example outer sleeve, in accordancewith aspects of this disclosure.

FIG. 7b is a side view of the example outer sleeve shown in FIG. 7 a.

FIG. 7c is a side cross section of the example outer sleeve shown inFIG. 7b , along line 7 c-7 c.

FIG. 8 is a perspective view of an example retaining ring, in accordancewith aspects of this disclosure.

FIG. 9a is a perspective view of an example insulator, in accordancewith aspects of this disclosure.

FIG. 9b is a side view of the example insulator shown in FIG. 9 a.

FIG. 10a is a side view of the assembled example gas diffuser assemblyshown in FIG. 4.

FIG. 10b is a side cross section of the example gas diffuser assemblyshown in FIG. 10a , along the line 10 b-10 b.

FIG. 10c is a partially exploded side view of the example nozzleassembly of FIG. 3a , with the assembled gas diffuser assembly shown inFIG. 10 a.

FIG. 11 is a side view of another example gas diffuser assembly, inaccordance with aspects of this disclosure.

FIG. 12a is a perspective view of an example nozzle.

FIG. 12b is a side view of the example nozzle shown in FIG. 12 a.

FIG. 12c is a side cross section view of the example nozzle shown inFIG. 12b , along line 12 c-12 c.

FIG. 13a is a side view of another example nozzle, in accordance withaspects of this disclosure.

FIG. 13b is a partially transparent side view of the example nozzleshown in FIG. 13 a.

FIGS. 14a and 14b are perspective views of an example contact tip, inaccordance with aspects of this disclosure.

FIG. 14c is a side view of the example contact tip shown in FIG. 14 a.

FIG. 14d is a side cross section view of the example contact tip shownin FIG. 14c , along line 14 d-14 d.

FIG. 15a is a side view of a fully assembled nozzle assembly, inaccordance with aspects of this disclosure.

FIG. 15b is a side cross section of the fully assembled nozzle assemblyof FIG. 15a , along line 15 b-15 b.

FIG. 15c is an expanded side cross section view of a portion of thefully assembled nozzle assembly of FIG. 15 b.

FIG. 16 is a cross sectional view of an example nozzle assembly,illustrating weld spatter within the nozzle assembly, in accordance withaspects of this disclosure.

FIG. 17a is an exploded side view of another example nozzle assembly, inaccordance with aspects of this disclosure.

FIG. 17b is an exploded side cross section view of the example nozzleassembly shown in FIG. 17a along line 17 b-17 b.

FIG. 18a is a perspective view of another example gas diffuser, inaccordance with aspects of this disclosure.

FIG. 18b is a side view of the example gas diffuser shown in FIG. 18 a.

FIG. 18c is a side cross section view of the example gas diffuser shownin FIG. 18b , along line 18 c-18 c.

FIG. 19a is a perspective view of another example insulator, inaccordance with aspects of this disclosure.

FIG. 19b is a side view of the example insulator shown in FIG. 19 a.

FIG. 19c is a side cross section view of the example insulator shown inFIG. 19b , along line 19 c-19 c.

FIGS. 19d and 19e are perspective views of other example insulators, inaccordance with aspects of this disclosure.

FIG. 20a is a perspective view of another example contact tip, inaccordance with aspects of this disclosure.

FIG. 20b is a side view of the contact tip shown in FIG. 20 a.

FIG. 20c is a side cross section view of the contact tip shown in FIG.20b , along line 20 c-20 c.

FIG. 21a is a side view of an assembled example nozzle assembly, inaccordance with aspects of this disclosure.

FIG. 21b is a side cross section view of the assembled example nozzleassembly shown in FIG. 21a , along line 21 b-21 b.

FIGS. 22a-22c are side cross section views of an example nozzleassembly, illustrating varying distances between an example contact tipand nozzle of the example nozzle assembly in proportion to a varyingaxial shoulder length of an example gas diffuser assembly of the nozzleassembly, in accordance with aspects of this disclosure.

FIG. 23 is a block diagram illustrating an example method of adjusting aposition of a contact tip relative to a nozzle, in accordance withaspects of this disclosure.

The figures are not necessarily to scale. Similar or identical referencenumerals may be used to refer to similar or identical components.

DETAILED DESCRIPTION OF THE INVENTION

Preferred examples of the present disclosure may be describedhereinbelow with reference to the accompanying drawings. In thefollowing description, well-known functions or constructions are notdescribed in detail because they may obscure the disclosure inunnecessary detail. For this disclosure, the following terms anddefinitions shall apply.

As utilized herein, “and/or” means any one or more of the items in thelist joined by “and/or”. As an example, “x and/or y” means any elementof the three-element set {(x), (y), (x, y)}. In other words, “x and/ory” means “one or both of x and y”. As another example, “x, y, and/or z”means any element of the seven-element set {(x), (y), (z), (x, y), (x,z), (y, z), (x, y, z)}. In other words, “x, y and/or z” means “one ormore of x, y and z”.

As utilized herein, the term “exemplary” means serving as a non-limitingexample, instance, or illustration. As utilized herein, the terms“e.g.,” and “for example” set off lists of one or more non-limitingexamples, instances, or illustrations.

As used herein, the term “processor” means processing devices,apparatuses, programs, circuits, components, systems, and subsystems,whether implemented in hardware, tangibly embodied software, or both,and whether or not it is programmable. The term “processor” as usedherein includes, but is not limited to, one or more computing devices,hardwired circuits, signal-modifying devices and systems, devices andmachines for controlling systems, central processing units, programmabledevices and systems, field-programmable gate arrays,application-specific integrated circuits, systems on a chip, systemscomprising discrete elements and/or circuits, state machines, virtualmachines, data processors, processing facilities, and combinations ofany of the foregoing. The processor may be, for example, any type ofgeneral purpose microprocessor or microcontroller, a digital signalprocessing (DSP) processor, an application-specific integrated circuit(ASIC). The processor may be coupled to, or integrated with a memorydevice.

The terms “coupled,” “coupled to,” and “coupled with” as used herein,each mean a structural and/or electrical connection, whether attached,affixed, connected, joined, fastened, linked, and/or otherwise secured.The term “attach” means to affix, couple, connect, join, fasten, link,and/or otherwise secure. The term “connect,” means to attach, affix,couple, join, fasten, link, and/or otherwise secure.

The terms “about” and/or “approximately,” when used to modify ordescribe a value (or range of values), position, orientation, and/oraction, mean reasonably close to that value, range of values, position,orientation, and/or action. Thus, the embodiments described herein arenot limited to only the recited values, ranges of values, positions,orientations, and/or actions but rather should include reasonablyworkable deviations.

As used herein, the term “front” means closer to a welding point, while“rear” means farther from a welding point.

Some examples of the present disclosure may relate to a gas diffuserassembly for a welding torch. The gas diffuser assembly may include agas diffuser having an external surface configured to frictionallyengage an insulator so as to resist movement of the insulator relativeto the external surface, and an insulator affixed to the externalsurface of the gas diffuser.

In some examples, the external surface may comprise a grooved, knurled,textured, or cornered surface. In some examples, the insulator may be athermoset plastic insulator. In some examples, the insulator may be asilicone based thermoset plastic insulator. In some examples, an outersleeve may be fit over the insulator, and the insulator may couple theouter sleeve to the gas diffuser. In some examples, the outer sleeve maycomprise a metal material. In some examples, the external surface of thegas diffuser may comprise a grooved surface, the outer sleeve maycomprise an internal grooved surface, and the insulator may be moldedinto the grooves of the outer sleeve and the gas diffuser. In someexamples, the insulator may be overmolded or injection molded over theexternal surface of the gas diffuser. In some examples, the outer sleevemay comprise one or more engagement features configured to mate with oneor more complementary engagement features of a nozzle. In some examples,the insulator may comprise one or more engagement features configured tomate with one or more complementary engagement features of a nozzle.

Some examples of the present disclosure may relate to an arc weldingtorch, comprising a body, a gooseneck coupled to the body, a gasdiffuser assembly coupled to the gooseneck, a contact tip retained bythe gas diffuser assembly, and a nozzle coupled to the gas diffuserassembly. The gas diffuser assembly may comprise a gas diffuser havingan external surface configured to frictionally engage an insulator so asto resist movement of the insulator relative to the external surface.The gas diffuser may further comprise an insulator affixed to theexternal surface of the gas diffuser. The insulator may be configured toinsulate the nozzle from electrical current conducted through the gasdiffuser.

In some examples, the external surface of the gas diffuser may comprisea grooved, knurled, textured, or cornered surface. In some examples, theinsulator may be a thermoset plastic insulator. In some examples, theinsulator may be a silicone based thermoset plastic insulator. In someexamples, an outer sleeve may be fit over the insulator, where theinsulator couples the outer sleeve to the gas diffuser. In someexamples, the outer sleeve may comprise a tapered shoulder configured tomate with a complementary taper of the nozzle, where a width of theshoulder determines a position of the nozzle with respect to the contacttip.

Some examples of the present disclosure may relate to a method ofmodifying a position of a contact tip relative to a nozzle. The methodmay comprise the steps of providing a welding torch having alongitudinal axis. The welding torch may comprise a nozzle having afront end and a rear end, a first gas diffuser assembly coupled to thenozzle, and a contact tip coupled to the first gas diffuser assembly.The first gas diffuser assembly may comprise a first shoulder that abutsthe rear end of the nozzle, thereby preventing the nozzle from movingaxially beyond the shoulder. The first shoulder may have a first axiallength. A front end of the contact tip may be spaced from the front endof the nozzle by a first distance. The method may further comprise thestep of replacing the first gas diffuser assembly with a second gasdiffuser assembly. The second gas diffuser assembly may comprise asecond shoulder having a second axial length that is different from thefirst axial length. The front end of the contact tip may be spaced fromthe front end of the nozzle by a second distance that is different fromthe first distance.

In some examples, the difference between the first distance and thesecond distance may be equal to the difference between the first axiallength and the second axial length. In some examples, the contact tipmay be retained entirely within the nozzle when the contact tip iscoupled to the first gas diffuser, and the contact tip may not retainedentirely within the nozzle when the contact tip is coupled to the secondgas diffuser. In some examples, the contact tip may be retained entirelywithin the nozzle when the contact tip is coupled to the second gasdiffuser, and the contact tip may not be retained entirely within thenozzle when the contact tip is coupled to the first gas diffuser.

Disclosed examples provide a heavy duty nozzle that provides the same orbetter performance than conventional heavy duty nozzles, while beingsmaller than conventional heavy duty nozzles. The disclosed examplenozzles also substantially reduce the amount of spatter that reachesand/or adheres to gas holes in the nozzle (deemed to be the mostcritical area to keep clear of spatter), while also reducing the amountof spatter that reaches and/or adheres to an internal area of the nozzleproximate the gas holes.

The location of the gas holes on the gas diffuser allow for easiercleaning. The gas holes are positioned on edges of a hexagonal hub ofthe diffuser, rather than on the flats of the diffuser. This makes iteasier for a reamer blade to get close enough to the gas holes to removespatter. Disclosed examples therefore improve the ease of cleaning forthe user.

Disclosed example nozzles have improved durability by making the nozzlea single part rather than an assembly of multiple parts. The singlepiece nozzle improves the durability of the nozzle due to theelimination of the G7 insulator of conventional welding torches. Inconventional weld torches, the G7 insulator breaks down over time fromexposure to the heat of the arc and causes the nozzle to wear. Disclosedexamples omit a G7 insulator from the nozzle, and include an insulatorin the gas diffuser assembly instead, thereby reducing the number ofnozzle parts.

FIG. 1 shows an example of a metal inert gas (MIG) welding system 10that may use any of the example diffusers, the example insulators, theexample nozzles, the example contact tips, the example welding torchassemblies, and/or the example method discussed below. While the weldingsystem 10 is a MIG welding system, other types of welding systems may beused. FIG. 1 illustrates a welding system 10 as including a power source12 coupled to a wire feeder 14. In the illustrated example, the powersource 12 is separate from the wire feeder 14, such that the wire feeder14 may be positioned at some distance from the power source 12 near awelding location. However, it should be understood that the wire feeder14, in some implementations, may be integral with the power source 12.The power source 12 may supply weld power to a torch 16 through the wirefeeder 14, or the power source 12 may supply weld power directly to thetorch 16. The wire feeder 14 supplies a wire electrode 18 (e.g., solidwire, cored wire, coated wire) to the torch 16. A gas supply 20, whichmay be integral with or separate from the power source 12, supplies agas (e.g., CO₂, argon) to the torch 16. An operator may engage a trigger22 of the torch 16 to initiate an arc 24 between the electrode 18 and awork piece 26. In some examples, the welding system 10 may be triggeredby an automation interface including, but not limited to, a programmablelogic controller (PLC) or robot controller. The welding system 10 isdesigned to provide welding wire (e.g., electrode 18), weld power, andshielding gas to the welding torch 16. As will be appreciated by thoseskilled in the art, the welding torch 16 may be of many different types,and may facilitate use of various combinations of electrodes 18 andgases.

The welding system 10 may receive data settings from the operator via anoperator interface 28 provided on the power source 12. The operatorinterface 28 may be incorporated into a faceplate of the power source12, and may allow for selection of settings such as the weld process(e.g., stick, TIG, MIG), the type of electrode 18 to be used, voltageand current settings, transfer mode (e.g., short circuit, pulse, spray,pulse), and so forth. In particular, the welding system 10 allows forMIG welding (e.g., pulsed MIG welding) with electrodes 18 (e.g., weldingwires) of various materials, such as steel or aluminum, to be channeledthrough the torch 16. The weld settings are communicated to controlcircuitry 30 within the power source 12.

The control circuitry 30 operates to control generation of welding poweroutput that is applied to the electrode 18 by power conversion circuitry32 for carrying out the desired welding operation. For example, in someexamples, the control circuitry 30 may be adapted to regulate a pulsedMIG welding regime that may have aspects of short circuit transferand/or of spray transfer of molten metal from the welding wire to amolten weld pool of a progressing weld. Such transfer modes may becontrolled during operation by adjusting operating parameters of currentand voltage pulses for arcs 24 developed between the electrode 18 andthe work piece 26.

The control circuitry 30 is coupled to the power conversion circuitry32, which supplies the weld power (e.g., pulsed waveform) that isapplied to the electrode 18 at the torch 16. The power conversioncircuitry 32 is coupled to a source of electrical power as indicated byarrow 34. The power applied to the power conversion circuitry 32 mayoriginate in the power grid, although other sources of power may also beused, such as power generated by an engine-driven generator, batteries,fuel cells or other alternative sources. Components of the powerconversion circuitry 32 may include choppers, boost converters, buckconverters, inverters, and so forth.

The control circuitry 30 controls the current and/or the voltage of theweld power supplied to the torch 16. The control circuitry 30 maymonitor the current and/or voltage of the arc 24 based at least in parton one or more sensors 36 within the wire feeder 14 or torch 16. In someexamples, a processor 35 of the control circuitry 30 determines and/orcontrols the arc length or electrode extension based at least in part onfeedback from the sensors 36. The arc length is defined herein as thelength of the arc between the electrode 18 and the work piece 26. Theprocessor 35 determines and/or controls the arc length or electrodeextension utilizing data (e.g., algorithms, instructions, operatingpoints) stored in a memory 37. The data stored in the memory 37 may bereceived via the operator interface 28, a network connection, orpreloaded prior to assembly of the control circuitry 30. Operation ofthe power source 12 may be controlled in one or more modes, such as aconstant voltage (CV) regulation mode in which the control circuitry 30controls the weld voltage to be substantially constant while varying theweld current during a welding operation. That is, the weld current maybe based at least in part on the weld voltage. Additionally, or in thealternative, the power source 12 may be controlled in a current controlmode in which the weld current is controlled independent of the weldvoltage. In some examples, the power source 12 is controlled to operatein a constant current (CC) mode where the control circuitry 30 controlsthe weld current to be substantially constant while varying the weldvoltage during a welding operation.

FIG. 2 is a side view of an example of a welding torch 16 of the MIGwelding system of FIG. 1, which may use any of the example gasdiffusers, the example insulators, the example nozzles, the example gasdiffuser assemblies, the example nozzle assemblies, and/or the examplecontact tips discussed below. As discussed in relation to FIG. 1, thetorch 16 includes the trigger 22 for initiating a weld and supplying theelectrode 18 to the weld. Specifically, the trigger 22 is disposed on ahandle 38. A welding operator holds the handle 38 when performing aweld. At a first end 40, the handle 38 is coupled to a cable 42 wherewelding consumables (e.g., the electrode, the shielding gas, and soforth) are supplied to the weld. Welding consumables generally travelthrough the handle 38 and exit at a second end 44, which is disposed onthe handle 38 at an end opposite from the first end 40.

The torch 16 includes a gooseneck 46 extending out of the second end 44of the handle 38. As such, the gooseneck 46 is coupled between thehandle 38 and a welding nozzle 48. As should be noted, when the trigger22 is pressed or actuated, welding wire (e.g., electrode 18) travelsthrough the cable 42, the handle 38, the gooseneck 46, and the weldingnozzle 48, so that the welding wire extends out of an end 50 (i.e.,torch tip) of the welding nozzle 48. Further, as illustrated in FIG. 2,the handle 38 is secured to the gooseneck 46 via fasteners 52 and 54,and to the cable 42 via fasteners 52 and 54. The welding nozzle 48 isillustrated with a portion of the welding nozzle 48 removed to show theelectrode 18 extending out of a contact tip 56 that is disposed withinthe welding nozzle 48. While the example torch 16 illustrated in FIG. 2is designed for welding by a human operator, one or more torchesdesigned for use by a robotic welding system may alternatively, oradditionally, be used with the welding system of FIG. 1. For example,the torch 16 may be modified to omit the trigger 22, may be adapted forwater cooling, etc. The example torch 16 illustrated in FIG. 2 may alsobe used with any of the example gas diffusers, the example insulators,the example nozzles, the example gas diffuser assemblies, the examplenozzle assemblies, and/or the example contact tips discussed below.

FIG. 3a is an exploded side view of an example nozzle assembly 300, suchas might be used with the welding torch 16 and/or welding system 10. Thenozzle assembly 300 may be coupled to a gooseneck 346 of the weldingtorch 16. The nozzle assembly 300 includes a nozzle 348, a contact tip356, and a gas diffuser assembly 400. When assembled, the components ofthe nozzle assembly 300 share a longitudinal axis 302 that extendsthrough an approximate middle of the nozzle assembly 300. FIG. 3b is across-sectional view of the example exploded nozzle assembly 300 of FIG.3 a.

FIG. 4 is an exploded perspective view of an example gas diffuserassembly 400. The gas diffuser assembly 400 includes a gas diffuser 500,an insulator 900, a retaining ring 800, and an outer sleeve 700. Whenassembled, the gas diffuser assembly 400 provides insulation to thenozzle assembly 300, which allows a single piece nozzle 348 to be usedrather than requiring a separate insulator directly coupled to thenozzle 348. The gas diffuser 500 also includes engagement features thatallow for a single nozzle to be used for varying types and/or sizes ofcontact tips and/or various desired contact tip stick-out (e.g.protruding from nozzle, recessed within nozzle, or flush with nozzle).

FIGS. 5a-5d show various views of the example gas diffuser 500. The gasdiffuser 500 acts as an interface between the gooseneck 346 and thecontact tip 356. The gas diffuser 500 is configured to transferelectrical energy to the contact tip 356 from the gooseneck 346 andtransfer heat energy from the contact tip 356 back into the gooseneck346. While other components may cooperate with the gas diffuser 500, thegas diffuser 500 provides the primary transmission path for heat andelectrical current between the contact tip 356 and the gooseneck 346. Toincrease the amount of electrical and heat energy transferred, the gasdiffuser 500 may be constructed using an electrically conductive and/orthermally conductive material. Examples of potential materials includebrass, bronze (e.g. C314 bronze), steel, aluminum, and/or copper. Insome examples, the gas diffuser 500 may be constructed using othermaterials and/or alloys that offer similar or better thermal and/orelectrical properties.

In some examples, the gas diffuser 500 includes a base 502 at the rearend 504 of the gas diffuser 500, a nose 506 at the front end 508 of thegas diffuser 500, and a hub 510 that couples the nose 506 to the base502. A bore (and/or passage) 511 extends through an approximate middle(and/or center) of the gas diffuser 500. The bore 511 extends from thefront end 508 through to the rear end 504. The bore 511 accommodatesmovement of welding consumables (e.g. wire electrode 18 and/or shieldinggas) from the gooseneck 346 through the gas diffuser 500 and/or gasdiffuser assembly 400. The example bore 511 includes multiple sectionsalong a length of the bore 511, each section having a respectivediameter.

In some examples, the gas diffuser 500 is configured to be coupled tothe gooseneck 346 through the base 502 of the gas diffuser 500. The base502 of the gas diffuser 500 is approximately cylindrical, though it maybe formed in different shapes in other examples. The base 502 of the gasdiffuser 500 may include screw threads 512 on an internal surface 514 ofthe gas diffuser 500. The screw threads 512 may be configured to engagematching screw threads on an external surface of the gooseneck 346, soas to couple the gas diffuser 500 to the gooseneck 346. The base 502 mayfurther include a taper 516 on the internal surface 514 of the base 502.The taper 516 narrows the diameter of the bore 511, such that the bore511 has a larger diameter towards the rear end 504 of the gas diffuser500, proximate the screw threads 512, and a smaller diameter towards themiddle of the gas diffuser 500, proximate a hub 510. The taper 516 maybe configured to engage a matching taper on the gooseneck 346, so as tofrictionally fit the gooseneck 346 within the base 502 and lock thegooseneck 346 in place. In some examples, the base 502 may includedifferent and/or additional engagement features to secure the gasdiffuser 500 to the gooseneck 346.

In some examples, the base 502 of the gas diffuser 500 may includefeatures configured to frictionally engage a material so as to resistmovement of the material relative to the external surface. In someexamples, these features may include grooves 518 on an external surface520 of the gas diffuser 500. In the example of FIGS. 5a-5d , the grooves518 are formed helically. The grooves 518 use two patterns, a clockwisepattern and a counter clockwise pattern. Radial grooves are formed ateach end of the helix. The grooves 518 provide space into which theinsulator 900 may be molded during an injection molding process or anover molding process. Molding the insulator 900 into the grooves 518 mayimprove the mechanical bond between the insulator 900 and the gasdiffuser 500, and keep the whole gas diffuser assembly 400 together whentorque and/or tension/compression is applied to the gas diffuserassembly 400. In some examples, knurling may be included instead of, orin addition to, the grooves 518, so as to provide a textured surfaceinto which the insulator 900 material may be molded. In some examples, acornered surface may be included instead of, or in addition to, knurlingor grooves 518, such that the insulator 900 may be molded around thecorners, which still might provide more of frictional engagement thanmolding the insulator 900 onto a smooth rounded surface. In someexamples, vapor deposition, additive manufacturing, and/or other methodsbesides molding may be used to affix the insulator 900 to the gasdiffuser 500.

In some examples, the gas diffuser 500 may include a hub 510 with apolygon profile. While different types of polygons may be used (e.g.triangle, square, octagon, pentagon, etc.), in the example shown inFIGS. 5a-5d , the hub 510 is formed with a hexagonal profile, having sixflat sides 522 (or flats) and six edges 524, with one edge 524 betweenevery two flats 522 and/or one flat 522 between every two edges 524. Gasholes 526 (and/or ports) extend through each edge 524 of the hub 510.More particularly, the gas holes 526 are positioned so that a center ofeach gas hole 526 is positioned approximately along an edge 524 of thehub. Thus, if one were to project the edge 524 through the gas hole 526,the edge 524 would approximately bisect the gas hole 526, splitting itinto two halves. In some examples, each half of a gas hole 526 mayextend at least partially through a portion of an adjacent flat 522.Positioning the gas holes 526 on the edges 524 of the hub 510 allow foreasier and/or more effective cleaning of the gas holes 526 than if thegas holes 526 were on the flats 522. When using a reamer to clean offspatter adhering to the inside of a nozzle 348, the jutting edges 524(or points on a 2D hexagon) may make easier targets than the flats 522.In some examples, however, the gas holes 526 may be positioned such thatthe gas holes 526 extend entirely through the flats 522, rather than theedges 524, and/or through portions of the nose 506 (as shown for examplein FIG. 5b ). However, locating the gas holes 526 entirely on the flats522 or on the rounded surface of the nose 506 may be less conducive toproper cleaning, because the reamer blade may not be able to getsufficiently close to thoroughly clean the gas holes 526.

While six gas holes 526 are contemplated by the hexagonal hub 510example of FIG. 5a , any number of gas holes 526 may be used (e.g. 1, 2,3, 5, 8, 10, 12, etc.). The gas holes 526 may be positioned and/ororiented such that fluid flows radially through the gas holes 526 (e.g.approximately perpendicular to the longitudinal axis 302). The gas holes526 may provide a flow path for fluid (e.g. shielding gas) to flow fromthe bore 511 within the gas diffuser 500 to the internal cavity space ofthe nozzle 348, when the gas diffuser 500 is positioned within thenozzle 348. Disclosed nozzles 348 have sufficient space within thenozzles 348 to enable the shielding gas coming out of the gas diffuser500 to equalize and become laminar before the gas exits the nozzle 348.A large cross-sectional area of the gas holes 526 may help reduce theamount of back pressure in the assembled torch 16, which may reduce thechance of gas leaking through cracks/gaps/holes in the torch/cableassembly.

In some examples, the gas diffuser 500 may include a nose 506 positionedforward and/or distal of the hub 510 and the base 502. In the example ofFIGS. 5a-5d , the nose 506 is approximately tubular, having acylindrical profile with a bore 511 extending through its approximatemiddle. The example nose 506 is configured for attachment to the contacttip 356. In some examples, the nose 506 may include a taper 528 alongthe internal surface 514 of the gas diffuser 500, proximate to the frontend of the gas diffuser 500. The taper 528 is configured to engage witha matching taper 528 of the contact tip 356, so as to retain the contacttip 356 within the nose 506. More particularly, the taper 528 of thenose 506 may decrease the diameter of the bore 511 when traveling inwardin a direction proceeding from the front end 508 of the gas diffuser 500towards the hub 510, such that the bore 511 has a larger diameter at thefront end 508 of the gas diffuser 500, and a smaller diameter towardsthe middle of the gas diffuser 500, closer to the hub 510. An externalsurface 520 of the gas diffuser 500 has a taper 530 sloped in anopposite direction proximate to the taper 528 on the interior surface514 of the gas diffuser 500. The taper 528 of the nose 506 of the gasdiffuser 500, through its interaction with the mating taper 366 on thecontact tip 326, may aid in the alignment (e.g., concentricity) of thecontact tip 356 when it is installed (e.g., threaded) into the gasdiffuser 500.

In some examples, the inner surface 514 of the nose 506 may also includethreading 532 configured to engage matching threading on the contact tip326, so as to couple the contact tip 356 to the gas diffuser 500. Thethreading 532 may be quick turn threading configured to allow for thecontact tip 356 to be secured with less than one complete turn. Thethreading 532 and taper 528 cooperate to retain the contact tip 356within the nose 506 of the gas diffuser 500.

In some examples, a diffuser insert 600, such as the diffuser insert 600shown in FIGS. 6a-6d , may be used with the gas diffuser 500. The insert600 may be used in examples where the gas diffuser 500 is used with awelding torch liner 1702 (such as shown in FIGS. 17a and 17b , forexample). In such examples, the insert 600 may be positioned within thebase 502 of the gas diffuser 500. The gas diffuser 500 may be configuredinternally to interact with the insert 600 such that a welding torchliner 1702 may not abut, reside within, nor be in any physical contactwith a proximal axial end 368 of the contact tip 356. In certainexamples, the contact tip 356 and the insert 600 may each have an outerdiameter that is substantially similar to the other such that the axialflow of welding gas is not impeded. In some examples, the insert 600 maybe integral with the gas diffuser 500.

As illustrated, in certain examples, the insert 600 may include anexternal shoulder 602 configured to abut the taper 516 on the internalsurface 514 of the base 502 of the gas diffuser 500, to hold the insert600 in place with respect to the gas diffuser 500 when the gas diffuser500 is coupled to the gooseneck 346. In addition, in certain examples,arms 604 of the insert 600 may facilitate the flow of welding gasthrough the welding torch 16 by having an outer diameter that generallymatches (e.g., is substantially similar to) the outer diameter of thenon-threaded proximal end portion 368 of the contact tip 356 illustratedin FIGS. 14a-14c . Furthermore, as illustrated, in certain examples, theinsert 600 may include one or more conduits 606 that facilitate the flowof the welding gas from the interior of the gooseneck 346 into theinternal bore of the gas diffuser 500. The insert 600 may furtherinclude a liner stop 608 configured to abut the liner 1702.

FIGS. 7a-7c illustrate various views of an outer sleeve 700 of the gasdiffuser assembly 400. The outer sleeve may be important for thedurability and structural integrity of the diffuser assembly whenimpacts and shocks are applied. Thus, the outer sleeve 700 may be formedof a strong durable material, such as a metal material, like brass,copper, steel, aluminum, etc. In the examples shown in FIGS. 7a-7c , theouter sleeve 700 is generally tubular, with an exterior wall 702surrounding a hollow interior 704. The exterior wall 702 of the outersleeve 700 includes a rear shoulder 706, a main body 708, a ring groove710, and a front rim 712. The outer diameter 706D of the outer sleeve700 is largest proximate the rear shoulder 706. The outer diameter 710Dis smallest in the area of the ring groove 710. The outer diameters712D, 708D of the front rim 712 and main body 708 are approximatelyequal. Both outer diameters 712D, 708D are smaller than the outerdiameter 706D of the rear shoulder 706 and larger than the outerdiameter 710D of the ring groove 710.

The rear shoulder 706 is connected to the main body 708 through a taper714. The taper 714 is configured to engage with a matching taper 322 ofthe nozzle 348. The taper 714 and shoulder 706 are configured to helpcenter the nozzle 348 to the contact tip 356 and provide a seal to thenozzle assembly 300 to prevent the shielding gas from escaping out theback of the nozzle 348. When the gas diffuser assembly 400 is insertedin the nozzle 348, the shoulder 706 of the gas diffuser abuts against arear portion of the nozzle 348, thereby preventing the nozzle 348 frommoving axially towards the gooseneck 346.

In some examples, a ring groove 710 may be formed as a recess in theexterior wall 702 of the outer sleeve 700. In some examples, the ringgroove 710 is sized and configured to hold a retaining ring 800. Whenthe gas diffuser assembly 400 is inserted into the nozzle 348,protrusions 804 on the retaining ring 800 (sitting in the ring groove710) are configured to snap fit into a groove of the nozzle 348. Thering groove 710 is positioned such a way as to provide a small amount offorce towards the taper when the retaining ring is “snapped” into thegroove of the nozzle 348. The retaining ring 800 and rear shoulder 706cooperate to retain the nozzle 348 on the gas diffuser assembly 400 viathe outer sleeve 700. In some examples, the retaining ring 800 may bereplaced by a retaining clip or some other engagement mechanism.

By reconfiguring an axial length 706L of the shoulder 706 (while keepingthe axial length of the body 702 between the ring groove 710 and theshoulder 706 the same), the position of the contact tip 356 with respectto the nozzle 348 (i.e. recessed, protruding, flush) can be changedwithout changing the nozzle 348. For instance, by increasing the axiallength 706L of the shoulder 706, the outer sleeve 700 may be extendedfarther over the gas diffuser 500, such that the front rim 712, ringgroove 710, and taper 714 all become closer to the front end 508 of thegas diffuser 500. Therefore, the nozzle 348 will connect to the outersleeve 700 farther forward, while the contact tip 356 will connect tothe gas diffuser 500 at the same position as before. Thus, the positionof the nozzle 348 will move forward with respect to the contact tip 356,making it more likely the contact tip 356 will be recessed within thenozzle 348. By decreasing the axial length 706L of the shoulder 706, theouter sleeve 700 may extend a shorter distance over the gas diffuser500, such that the front rim 712, ring groove 710, and taper 714 allbecome farther from the front end 508 of the gas diffuser 500.Therefore, the nozzle 348 will connect to the outer sleeve 700 fartherbackward, while the contact tip 356 will connect to the gas diffuser 500at the same position as before. Thus, the position of the nozzle 348will move backward with respect to the contact tip 356, making it morelikely the contact tip 356 will stick-out or protrude past the front end306 of the nozzle 348. Rather than changing the nozzle 348 to change theposition of the contact tip 356 with respect to the nozzle 348 (i.e.recessed, protruding, flush), the gas diffuser assembly 400 may bechanged instead.

In some examples, the axial length 706L of the shoulder 706 may bealtered without keeping the axial length of the body 708 between thering groove 710 and the shoulder 706 the same. In such an example, forinstance, the nozzle 348 may be configured with grooves and/or otherengagement features at different points along its length, in order toaccommodate different type diffusers.

An interior wall 716 of the outer sleeve 700 may be formed with featuresconfigured to frictionally engage a material so as to resist movement ofthe material relative to the outer sleeve 700. In some examples, thesefeatures may include grooves 718 on an interior wall 716 of the outersleeve 700. The grooves 718 may be configured to be complementary to thegrooves 518 of the gas diffuser 500. Thus, the grooves 718 may also beformed helically using a clockwise pattern and/or a counter clockwisepattern, with radial grooves formed at each end of the helix. Thegrooves 718 may provide space into which the insulator 900 may be moldedduring an injection molding process or an over molding process, asdiscussed further below. Molding the insulator 900 into the grooves 718and grooves 518 may improve the mechanical bond between the insulator900, the gas diffuser 500, and the outer sleeve 700, and keep the wholegas diffuser assembly 400 together when torque and/ortension/compression is applied to the gas diffuser assembly 400. In someexamples, knurling may be included instead of, or in addition to, thegrooves 718, so as to provide a textured surface into which theinsulator 900 material may be molded. In some examples, a corneredsurface may be included instead of, or in addition to, knurling orgrooves 718, such that the insulator 900 may be molded around thecorners, which still might provide more of frictional engagement thanmolding the insulator 900 onto a smooth rounded surface. In someexamples, vapor deposition, additive manufacturing, and/or other methodsbesides molding may be used to affix the insulator 900 to the outersleeve 700.

FIG. 8 illustrates an example retaining ring 800. In some examples, theretaining ring 800 may be sized to fit in the ring groove 710 of theouter sleeve 700. In some examples, the retaining ring 800 may becomprised of an approximately annular collar 802. While the retainingring 800 is shown as being discontinuous in FIG. 8, with a gap G in itscollar 802, in other examples the retaining ring 800 may be fullycontinuous, with no gap G, and/or with a clasp and/or other releasableconnector that can connect and/or disconnect the two sides of the collar802 across the gap G. In some examples, the retaining ring 800 mayinclude protrusions 804 (and/or protuberances, bumps, humps, ridges,bulges, etc.) extending outward from the collar 802. The protrusions 804may be approximately half spherical, or some other appropriate shape.The protrusions 804 may be approximately centered around thecircumference of the retaining ring 800. The protrusions 804 may beconfigured to engage a complementary groove 328 on an internal surfaceof the nozzle 348 to couple the nozzle 348 to the gas diffuser assembly400. Conveniently, the retaining ring 800 may give the user positivefeedback (e.g. an audible “click”) when the protrusions 804 engage thecomplementary groove 328 to indicate that the nozzle 348 is secured ontothe gas diffuser assembly 400. While approximately four separateprotrusions 804 are shown in the example of FIG. 8, in other examplesthe retaining ring 800 may have more or less protrusions 804.

FIGS. 9a and 9b illustrate various views of an example insulator 900.The example insulator 900 is approximately tubular, with a hollowinterior. The insulator 900 has a forward rim 902, a main body 904, afirst shoulder 906, a second shoulder 908, and a rear rim 910. The shapeand/or form of the insulator 900 approximately corresponds to the shapeand/or form of the space and/or void between the gas diffuser 500 andthe outer sleeve 700. During assembly of the gas diffuser assembly 400,the insulator 900 may be injection molded into the space between the gasdiffuser 500 and the outer sleeve 700. During the injection moldingprocess, the insulator 900 may be pushed into the space between the gasdiffuser 500 and the outer sleeve, including the space in the grooves518 of the gas diffuser 500 and the grooves 718 of the outer sleeve 700.Thus, while the insulator 900 is shown as being in this one particularform, the insulator 900 may take on other forms depending on the form ofthe gas diffuser 500, the outer sleeve 700, and the space in between. Insome examples, the insulator 900 may be overmolded onto the gooseneck346 instead of the gas diffuser 500. However, this variation may requireusers to replace the gooseneck 346 if the insulator 900 fails, which mayoccur before the gooseneck 346 itself requires replacement.

In some examples, the insulator 900 may be formed of an electricallyinsulating material configured to isolate the electrical current betweenthe gas diffuser 500 and the nozzle 348, and/or between the gas diffuser500 and the gooseneck 346. In some examples, the insulator 900 may alsobe configured to act as a medium to transfer heat energy from the nozzle348 back into the gooseneck 346. Without this gateway to transfer heatenergy, the nozzle 348 may become much hotter during operation. In somecases, fiberglass-resin materials that resist heat and have a highdielectric strength may be used as insulating material. In some cases,ceramic material may be used for the insulator. In some examples, theinsulator 900 may be formed of a thermoset plastic. In some examples,the insulator 900 may be formed of a silicone based thermoset plastic.The thermoset plastic may enable the insulator 900 to maintain itsstrength during high heat operation (e.g. 450-500 degrees Celsius) andstill have high impact strength. Once molded into the space between thegas diffuser 500 and the outer sleeve 700, the thermoset material maysignificantly strengthen the gas diffuser assembly 400 and the nozzleassembly 300.

FIGS. 10a and 10b illustrate various views of a fully assembled gasdiffuser assembly 400. As shown, gas diffuser assembly 400 is assembledonto a portion of the gooseneck 346. In particular, the first shoulder906, second shoulder, 908, and rear rim 910 of the insulator 900 are fitover the gooseneck 346. The outer sleeve 700 is fit over the insulator900. The insulator 900 fills the space between the outer sleeve 700 andthe gas diffuser 500. The retaining ring 800 sits in the ring groove 710of the outer sleeve 700. The front rim 712 of the outer sleeve 700extends over and past the body 502 of the gas diffuser 500. In someexamples, the front rim 712 may extend farther past the body 502 of thegas diffuser 500, be flush with the end of the body 502 of the gasdiffuser 500, or be retracted behind the body 502 of the gas diffuser500, depending on the axial length 706L of the rear shoulder 706 of theouter sleeve 700. The insulator 900 may be molded all the way up to thefront rim 712 of the outer sleeve 700, so as to prevent bridging ofspatter from the gas diffuser 500 to the outer sleeve 700 and nozzle348. When assembled into the nozzle 348, the shoulder 706 of the outersleeve 700 and the protrusions 804 of the retaining ring 800 may act asengagement features configured to engage complementary engagementfeatures of the nozzle 348 so as to couple the gas diffuser assembly 400to the nozzle 348. FIG. 10c shows a partially exploded side view of thenozzle assembly 300, with the components of the gas diffuser assembly400 assembled together.

FIG. 11 illustrates a side view of an alternative example gas diffuserassembly 1100. The alternative gas diffuser assembly 1100 issubstantially identical to the gas diffuser assembly 400 except for itsengagement features. In particular, the outer sleeve 1102 has screwthreads 1104, rather than a ring groove 710 with a retaining ring 800having protrusions 804. The screw threads 1104 are configured to engagecomplementary threads 1320 on a nozzle, such as the alternative examplenozzle 1348 shown in FIG. 13b . The screw threads 1104 may be quick turnthreads configured to allow for the gas diffuser assembly 1100 to besecured to the nozzle with less than one complete turn. While the screwthreads 1104 shown in FIG. 11 are male threads, in some examples, thescrew threads 1104 may be female threads.

FIGS. 12a-12c show an example nozzle 348. The nozzle 348 provides amethod for directing shielding gas down onto the weld arc to protect itfrom contamination (oxidization/porosity in the weld). The nozzle 348creates a flow of shielding gas that is generally laminar, as turbulentair flow may increase the risk of weld pool contamination. In someexamples, the nozzle 348 may be configured with sufficient space withinthe interior of the nozzle 348 to allow the shielding gas coming out ofthe gas diffuser assembly 400 to equalize and become laminar before itexits the front bore of the nozzle 348. In some examples, the nozzle 348may be a one-piece design, rather than the three-piece design ofconventional welding torches. Thus, disclosed examples may increase thedurability of the nozzle 348 and decrease the assembly time.

In some examples, the nozzle 348 may have a rear end 304, a front end306, an external surface 308, and an internal surface 310. In theexample of FIGS. 12a-12c , the nozzle 348 includes a bore 312 extendingthrough the nozzle 348 along an axis 302 of the nozzle 348. The externalsurface 308 of the nozzle 348 is generally cylindrical and/or tubularalong an external body 314 of the nozzle 348, such that an outerdiameter 314D of external body 314 is approximately the same along theaxial length of the nozzle 348. The external body 314 of the nozzle 348extends from the rear end 304 of the nozzle 348 to a point more thanhalfway to the front end 306 of the nozzle 348. The nozzle 348 furtherincludes a tapering portion 316 extending from the endpoint of theexternal body 314 to the front end 306. The tapering portion 316 issloped such that the outer diameter 316D at the front end 306 of thenozzle 348 is less than the outer diameter 314D of the nozzle 348 at theexternal body 308.

The bore 312 of the nozzle 348 is at its largest at the rear end 304 ofthe nozzle. The bore 312 is smaller at a front end 306 of the nozzle348, such that the internal diameter 304D at the rear end 304 of thenozzle 348 is larger than the internal diameter 306D at the front end306D of the nozzle. A shoulder engaging taper 322 exists at the rear end304 of the nozzle 348, connecting the internal surface 310 of the nozzle348 to the external surface 308 of the nozzle 348. The taper 322 has anangled slope configured to match with and engage the angled slope of thetaper 714 of the outer sleeve 700 of the gas diffuser assembly 400.

The internal surface 310 of the nozzle 348 includes an internal bodyportion 318 that extends from a rear end 304 of the nozzle 348. Theinternal surface 310 of the nozzle at the internal body portion 318extends approximately parallel to the external surface 308. In someexamples, the internal body portion 318 includes an annular groove 320configured to engage protrusions 804 of the retaining ring 800. Thedistance between the rear end 304 of the nozzle 348 and the annulargroove 320 may be approximately equal to the axial length of the mainbody 708 of the outer sleeve 700, from the taper 714 to the ring groove710. In some examples, the nozzle 348 may include a plurality of annulargrooves 320 spaced at different distances, so as to accommodate gasdiffuser assemblies 400 having different axial lengths of the main body708 of the outer sleeve 700, from the taper 714 to the ring groove 710.The annular groove 320 and shoulder engaging taper 322 are configured toengage matching features of the gas diffuser assembly (i.e. protrusions804 of retaining ring 800 and taper 714 of shoulder 706 of outer sleeve700) so as to couple the nozzle 348 to the gas diffuser assembly 400.

At a narrowing neck 324 of the nozzle 348, the bore 304 and/or internalsurface 310 of the nozzle 348 narrows to a diameter 324D that is lessthan the diameter 304D at the rear end 304 of the nozzle 348. Thenarrowing neck 324 acts limits the amount of space in the nozzle 348 forspatter to travel. Thus, the narrowing neck 324 helps to prevent spatterfrom traveling into the body 318 of the nozzle 348 e, where the gasholes 526 of the gas diffuser assembly 400 may be positioned. Reducingthe amount of spatter capable of reaching beyond the narrowing neck 324to the gas holes 526, reduces the amount of spatter capable of cloggingand/or obstructing the gas holes 526. It is desirable to keep the gasholes 526 free from spatter as clogged gas holes may prevent shieldinggas from properly shielding the weld pool from contamination, therebyreducing weld quality. In some examples, the inner diameter 324D of thenarrowing neck 324 at its narrowest point is approximately equal to theinner diameter of the front end 306D of the nozzle 348. This may helpensure that a reamer that can enter through the front end 306 of thenozzle to clean the nozzle will be able to proceed past the narrowingneck 324 to clean spatter from in and/or around the gas holes 526. Inother examples, the inner diameter 324D of the narrowing neck 324 at itsnarrowest point may be larger or smaller than the inner diameter of thefront end 306D of the nozzle 348.

The inner surface 310 of the nozzle 348 includes a spatter deflector 328between the front end 306 of the nozzle 348 and the narrowing neck 324.The spatter deflector 328 comprises two sloped sections 330, 332. Afirst sloped section 330 slopes outward toward the external surface 314from the narrowing neck 324. The second sloped section 332 slopes inwardtoward the central axis 302 from the first sloped section 330 to thefront end 306 of the nozzle 348. In some examples the first slopedsection 330 may have a smaller length than the second sloped section332. For example, the first sloped section 330 may have a length between0.25 and 0.5 inches (such as 0.438 inches, for example). The secondsloped section 332 may have a length between 0.4 inches and 0.75 inches(such as 0.548 inches, for example). In some examples, the innerdiameter 328D at the widest point of the spatter deflector 328 is largerthan the inner diameter 306D of the nozzle 348 at the front end 306, andthe inner diameter 324D of the nozzle 348 at the narrowing neck 324D. Insome examples, the widest point of the spatter deflector 328, maycorrespond to the point where the external surface 308 transitions fromthe external body portion 314 to the tapering portion 316.

The wider diameter 324D of the spatter deflector 324 provides more spacefor shielding gas to slow down before exiting the nozzle 348, so as toensure laminar flow. The wider diameter 324D also provides more spacefor the spatter deflector 324 to trap spatter within the nozzle 348. Thesecond sloped section 332 expands the volume within the nozzle 348 toaccept more spatter. The first sloped section 322 then restricts thevolume within the nozzle to deflect and/or trap the spatter that hasentered the nozzle 348. Deflected spatter may lose enough of its energyto prevent adherence to the inside of the nozzle 348. Alternatively,deflected spatter may be deflected out of the nozzle 348 or onto asurface of the nozzle that is less critical and/or relatively easilycleaned. Once the gas diffuser assembly 400 and contact tip 356 areassembled into the nozzle, the contact tip 356 will take up some of thespace inside the nozzle, thereby also helping to deflect spatter. Thespace between the narrowing neck 324 and the gas diffuser assembly 400and/or contact tip 356 within the nozzle 348 may be small enough tolimit spatter entering past the narrowing neck 324, and wide enough toensure laminar gas flow. With such a small space at the narrowing neck324, there may be limited trajectories from the weld pool through thenarrowing neck 324 for spatter to follow. Additionally, the limitedamount of spatter that achieves such a trajectory would still have tohave sufficient velocity to propel it past the narrowing neck 324. Thus,the spatter deflector 324 may help to block, deflect, and/or trapspatter within the nozzle before it can proceed past the narrowing neck328 into a portion of the nozzle 348 proximate the gas holes 526, wherethe spatter could have a larger detrimental effect on performance.

FIGS. 13a and 13b show various views of another example nozzle 1348. Theexample nozzle 1348 is similar to the nozzle 348 in most respects. Thenozzle 1348 includes a spatter deflector 328 and a narrowing neck 324,as well as most other features of the nozzle 348. However, the nozzle1348 includes different engagement features for coupling the nozzle 1348to a diffuser assembly. More particularly, rather than an annular groove320 to engage protrusions 804 on the gas diffuser assembly 400, thenozzle 1348 includes a screw thread groove 1320 configured to engagecomplementary screw threads 1104 (e.g. screw thread protrusions) on agas diffuser assembly 1100 (such as the gas diffuser assembly 1100 shownin FIG. 11).

FIGS. 14a-14d show various views of a contact tip 356. The contact tip356 may be similar to the contact tip described in U.S. PatentPublication 2017/0165780 (Centner) which is owned by the assignee ofthis application, and is incorporated herein by reference. In someexamples, the contact tip 356 may include a bore 360 extending throughan approximate middle of the contact tip 356. The contact tip 356 mayinclude a rounded front face 362, which may reduce spatter adhesion. Insome examples, the contact tip 356 includes external threading 364configured to mate with internal threading 532 of the gas diffuser 500so as to couple the contact tip 356 to the gas diffuser 500. Thethreading 364 may be disposed near a center portion of the contact tip356. A tapered outer surface 366 of the contact tip 356 may beconfigured to abut a mating tapered inner surface 528 of the gasdiffuser 500 when the contact tip 356 is threaded into the gas diffuser500. The tapered outer surface 366 may be disposed near a center portionof the contact tip 356. A non-threaded proximal end portion 368 of thecontact tip 356 may be referred to as a “cooling tail.” The gas diffuser500 is configured such that when the contact tip 356 is installed withinthe gas diffuser 500, the non-threaded proximal end portion 368 of thecontact tip 356 (the “cooling tail”) protrudes into the welding gasstream and, as such, helps cool the contact tip 356 through convectionduring use, thereby improving the performance and/or service life of thecontact tip 356.

FIGS. 15a-15c show an example fully assembled nozzle assembly 300. Fullyassembled, the contact tip 356 is coupled to the gas diffuser assembly500 within the nozzle 348, and the gas diffuser assembly 500 is coupledto gooseneck 346. The gas diffuser assembly 400 provides an electricallyconductive pathway from the gooseneck 346 to the contact tip 356. Thetaper 714 and the protrusions 804 of the gas diffuser assembly 400engage the nozzle 348. In the example shown in FIG. 15b , the contacttip 356 is recessed behind a front end 306 of the nozzle 348. However,this may be changed by changing the axial length 706L of the shoulder706 of the gas diffuser assembly 400. By increasing the axial length706L of the shoulder 706, the positions of the taper 714 and theprotrusions 804 with respect to the gas diffuser 500 and the contact tip356 may be changed, such that the contact tip 356 may be made flush withthe front end 306 of the nozzle 348, or may be made to stick-out pastthe front end 306 of the nozzle 348.

FIG. 16 shows a cross sectional view of the fully assembled nozzleassembly 300, illustrating the behavior of the spatter deflector 328with respect to weld spatter. As shown in the figure, the gas holes 526of the gas diffuser assembly 400 are positioned behind the narrowingneck 324 of the nozzle 348, such that the spatter deflector 328 andnarrowing neck 324 will be able to minimize the amount of spatter thatmight obstruct the gas holes 526. A weld point 98 where a weld pool iscreated by the arc 24 is spaced from the contact tip 356 by a distanceD. The distance D may, for example, be approximately 15 millimeters (orapproximately 0.591 inches). Spatter is created at the weld point 98.The spatter may have potential example trajectories 97. Because of thecontact tip 356 and the structure of the nozzle 348, none of the exampletrajectories 97 will directly propel the spatter past the narrowing neck324 of the nozzle 348. Spatter following the trajectories 97 will eitherbe propelled away from the nozzle 348 or will be propelled on acollision course with the contact tip 356 or the spatter deflector 328of the nozzle 348. If the weld point were farther from the contact tip356, there may be some example trajectories 97 that spatter could followthrough the narrowing neck 324. However, the farther away the weld point98 is from the nozzle 348, the more energy the spatter will need toachieve sufficient velocity to propel the spatter past the narrowingneck 324, which may reduce the energy of the spatter such that there islittle heat energy, which may cause the spatter to have a low adhesionforce. The majority of the spatter that makes it to the spatterdeflector 328 will either be deflected away or trapped by the spatterdeflector 328. Deflected spatter will lose both kinetic energy (i.e.velocity) and thermal energy, and will have less of a chance ofretaining enough energy to travel past the narrowing neck 324 toobstruct the gas holes 526. Spatter that accumulates in the nozzle 348proximate the spatter deflector 328 is easier to clean with a torchcleaner (e.g. a reamer), since the spatter deflector 328 is close to thefront end 306 of the nozzle, with minimal depth within the nozzle. Themajority of the spatter may accumulate between the first sloped section330 of the spatter deflector 328 and the nose 506 of the gas diffuser500.

FIGS. 17a and 17b show various views of another example nozzle assembly1700. The nozzle assembly 1700 is similar to the nozzle assembly 300. Insome examples, the nozzle assembly 1700 includes a nozzle 348, similarto the nozzle 348 of the nozzle assembly 300. In some examples, thenozzle 348 may be replaced by the nozzle 1348, discussed above. In someexamples, the nozzle assembly 1700 may include a contact tip 2000, and agas diffuser assembly 1800 that are different from the contact tip 356and gas diffuser assembly 400 discussed above. For example, the gasdiffuser assembly 1800 may have no outer sleeve 700. The nozzle assembly1700 may also be adapted to work with a liner 1702. The liner 1702 maybe trimmed flush with the end of the gas diffuser assembly 1800 toeliminate measuring of the liner 1702. FIGS. 21a and 21b show assembledviews of the nozzle assembly 1700. When assembled, the components of thenozzle assembly 1700 share a longitudinal axis 302 that extends throughan approximate middle of the nozzle assembly 1700.

FIGS. 18a-18c show various views of the gas diffuser 1802. The gasdiffuser 1802 is similar to the gas diffuser 400. In some examples, thegas diffuser 1800 may include gas holes 1826 positioned on the edges 524of polygon hub 510. In some examples, the gas holes 526 are more ovalthan the circular holes of the gas diffuser 1802. The increasedcross-sectional area of the oval gas holes 526 may help reduce theamount of back pressure in the assembled torch, which may reduce thechance of gas leaking through cracks/gaps/holes in the torch/cableassembly. The gas diffuser 1802 also includes a nose 1806 with screwthreads 1810 configured to engage matching threads on the contact tip2000. However, the screw threads 1810 are on an external surface of thegas diffuser 1802, rather than an internal surface. In some examples,the gas diffuser 1802 may include within the nose 1806 a liner guide1804 sized according to the outer diameter of the liner 1702. The linerguide 1804 may be configured to keep the liner 1702 concentric to thecontact tip 2000, to help with feedability.

FIGS. 19a-19c show various views of an insulator 1900. In some examples,the insulator 1900 functions as the electrical insulator between the gasdiffuser 1802 and the nozzle 348 and/or between the gas diffuser 1802and the gooseneck 346. The insulator 1900 may also act as a medium totransfer heat energy from the nozzle 348 back into the gooseneck 346. Inother examples, the insulator 1900 is overmolded onto the gas diffuser1802 to create one part to improve durability. The insulator 1900 mayinclude features to couple the nozzle 348 to the gas diffuser assembly1800. For example, as shown in FIGS. 19e , the insulator 1900 mayinclude a groove 1902 configured to fit a fastening feature, such as asnap ring 1910, an O-ring 1912, a retaining ring 800, or the like. Thefastening feature may be fitted onto the insulator 1900 through thegroove 1902 and mate with a complementary feature of the nozzle 346,such as an annular groove 320, to couple the nozzle 346 to the gasdiffuser assembly 1800. In some examples, the insulator 1900 may includea second groove 1904 to fit a retaining ring 800, fastener, O-ring,and/or a combination of retaining mechanisms. In some examples, such asshown in FIG. 19d , the insulator 1900 may additionally, oralternatively, include screw threads 1908 configured to engagematching/complementary threads 1320 in the nozzle 1348, such as shown inFIG. 13b , for example. The insulator 1900 may also include a shoulder1906 having an axial shoulder length 1906L configured to abut the nozzle348, similar to the shoulder 706 of the outer sleeve 700.

FIGS. 20a-20c show various views of an example contact tip 2000. Thecontact tip 2000 has a rounded front face 2002 to reduce spatteradhesion. The contact tip 2000 has a hexagon profile at its rear face2004, though other polygon profiles may be used rather than a hexagonprofile. The contact tip 2000 has a bore 2008 extending through anapproximate middle of the contact tip 2000. The bore 2008 is configuredto fit and feed wire 18. The contact tip 2000 has a liner recess 2006 atthe rear of the contact tip 2000. The liner recess 2006 may allow theliner 1702 to move within the liner guide 1804 without interfering withthe contact tip 2000. This feature may increase the feedability of thewire 18 as the liner 1702 can move freely and will not bind up when therobot is articulated

FIGS. 22a-22c show various views of an example nozzle assembly 300having gas diffuser assemblies 400 with different outer sleeves 700.Each outer sleeve 700 has a shoulder 706 with a different axial length706L. The distance D1 between the front face 362 of the contact tip 356and the front end 306 of the nozzle 348 vary in proportion to thevarying axial lengths 706L of the shoulders 706. Thus, the change in thedistance D1 between the front face 362 of the contact tip 356 and thefront end 306 of the nozzle 348 in FIGS. 22a-22c may be approximatelyequal to the change in the axial length 706L of the shoulder 706 of theouter sleeve 700. The distance D1 determines whether the contact tip 356is retracted within the nozzle 348 (as in FIG. 22a ), flush with thenozzle 348 (as in FIG. 22b ), or sticking out past the nozzle 348 (as inFIG. 22c ).

FIG. 23 shows an example method 2300 of adjusting a position of thecontact tip 356 relative to the nozzle 348 (e.g. stick out). Stick outis conventionally adjusted by changing the nozzle 348. A differentlength nozzle 348 may change how far the contact tip 356 protrudes past,or is recessed behind, the front end 306 of the nozzle 348. However,this may require a variety of different length nozzles 348. The methodof FIG. 23 contemplates changing the gas diffuser assembly 400/1800 toachieve a variety of different desired nozzle 348/1348 versus contacttip 356/2000 positions, while keeping the same nozzle 348/1348. Whilethe method may reference the specific torch 16 components, it should beunderstood that the method may use any combination of applicable torch16 components discussed above.

By using different gas diffuser assemblies 400 with different outersleeves 706 having shoulders 706 with different axial lengths 706L, theposition of the contact tip 356 relative to the nozzle 348 (e.g. stickout) maybe adjusted without having to use different nozzles 348. In step2302 of the method, an arc welding torch 16 is provided. The torch 16may have any of the above described nozzle assemblies 300/1700 and/orgas diffuser assemblies 400/1800, and/or their components. In step 2304,a desired distance between the front face 362 of the contact tip 356 andthe front end 306 of the nozzle 348 is determined. At step 2306, adetermination is made whether the actual distance D1 between the frontface 362 of the contact tip 356 and the front end 306 of the nozzle 348(e.g. contact tip stick out) is sufficient. This may involve measurementof the actual distance D1 as compared to the desired distance and/or adetermination whether the difference is within a certain negligibleand/or allowable deviation. The determination at step 2306 may furtherinvolve analyzing other available gas diffuser assemblies 400, the axiallengths 706L of their shoulders 706, and/or the anticipated change inactual distance D1 as result of replacement. In some examples, thedetermination at step 2306 may additionally involve analyzing thecurrent contact tip 356 and/or other available contact tips 356 todetermine the desirability of replacement. If the determination at step2306 is that the current distance D1 between the front face 362 of thecontact tip 356 and the front end 306 of the nozzle 348 is sufficient,the method moves to step 2310, where welding operations may be begun orresumed. If the determination at step 2306 is that the current distanceD1 between the front face 362 of the contact tip 356 and the front end306 of the nozzle 348 is not sufficient, then the gas diffuser assembly400 may be changed at step 2308 to a gas diffuser assembly 400 having ashoulder 706 with an axial length 706L that will bring the actualdistance D1 closer to the desired distance. Then the method may proceedto begin or resume welding operations at step 2310.

In some examples, the position of the contact tip 356 relative to thenozzle 348 (e.g. stick out) may be adjusted by changing the nozzle 348rather than the gas diffuser assembly 400. In such an example, thenozzle 348, rather than the gas diffuser assembly 400, may be changed instep 2308. For example, a first nozzle 348 having a first length(measured as the axial distance between the front end 306 of the nozzle348 and the rear end 304) may be replaced by a second nozzle 348 havinga second length that is different from the first length. The distance D1between the front face 362 of the contact tip 356 and the front end 306of the nozzle 348 would change in direct proportion to (and/or equallyto) the change in axial lengths between the two nozzles 348. However,the insulator 900 of the welding torch would remain the same because theinsulator 900 would be affixed to (and/or dependent on) the gas diffuser500 rather than the nozzle 348.

In some examples, the method of FIG. 23 may be implemented in a robotwelding system. In some examples, sensors may be used to determine theactual and/or desired contact tip 356 stick out distances D1. In someexamples, the memory 37 may store preloaded and/or dynamically measureddata relating to the available gas diffuser assemblies 400 and/or axiallengths 706L of the shoulders 706 of those assemblies. In some examples,the control circuitry 30 may be configured to assist in and/or takecharge of making the determinations of steps 2304 and/or 2306. In someexamples, operator input through the operator interface 28 may play arole in the determinations of steps 2304 and/or 2306. In some examples,control circuitry 30 may be configured to operate one or more actuators,robots, and/or other mechanisms to automatically disassemble and/orreassemble the nozzle assemblies 400 when implementing the method 2300.

While the present method and/or system has been described with referenceto certain implementations, it will be understood by those skilled inthe art that various changes may be made and equivalents may besubstituted without departing from the scope of the present methodand/or system. For example, block and/or components of disclosedexamples may be combined, divided, re-arranged, and/or otherwisemodified. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the presentdisclosure without departing from its scope. Therefore, the presentmethod and/or system are not limited to the particular implementationsdisclosed. Instead, the present method and/or system will include allimplementations falling within the scope of the appended claims, bothliterally and under the doctrine of equivalents.

What is claimed is:
 1. A gas diffuser assembly for a welding torch,comprising: a gas diffuser having an external surface configured tofrictionally engage an insulator so as to resist movement of theinsulator relative to the external surface; and an insulator affixed tothe external surface of the gas diffuser.
 2. The gas diffuser assemblyof claim 1, wherein the external surface comprises a grooved, knurled,textured, or cornered surface.
 3. The gas diffuser assembly of claim 1,wherein the insulator is a thermoset plastic insulator.
 4. The gasdiffuser assembly of claim 3, wherein the insulator is a silicone basedthermoset plastic insulator.
 5. The gas diffuser assembly of claim 1,further comprising an outer sleeve fit over the insulator, wherein theinsulator couples the outer sleeve to the gas diffuser.
 6. The gasdiffuser assembly of claim 5, wherein the outer sleeve comprises a metalmaterial.
 7. The gas diffuser assembly of claim 5, wherein the externalsurface of the gas diffuser comprises a grooved surface, wherein theouter sleeve comprises an internal grooved surface, and wherein theinsulator is molded into the grooves of the outer sleeve and the gasdiffuser.
 8. The gas diffuser assembly of claim 1, wherein the insulatoris overmolded or injection molded over the external surface of the gasdiffuser.
 9. The gas diffuser assembly of claim 5, wherein the outersleeve comprises one or more engagement features configured to mate withone or more complementary engagement features of a nozzle.
 10. The gasdiffuser assembly of claim 1, wherein the insulator comprises one ormore engagement features configured to mate with one or morecomplementary engagement features of a nozzle.
 11. An arc welding torch,comprising: a body; a gooseneck coupled to the body; a gas diffuserassembly coupled to the gooseneck, wherein the gas diffuser assemblycomprises a gas diffuser having an external surface configured tofrictionally engage an insulator so as to resist movement of theinsulator relative to the external surface, and wherein the gas diffuserfurther comprises an insulator affixed to the external surface of thegas diffuser; a contact tip retained by the gas diffuser assembly; and anozzle coupled to the gas diffuser assembly, wherein the insulator isconfigured to insulate the nozzle from electrical current conductedthrough the gas diffuser.
 12. The arc welding torch of claim 11, whereinthe external surface of the gas diffuser comprises a grooved, knurled,textured, or cornered surface.
 13. The arc welding torch of claim 11,wherein the insulator is a thermoset plastic insulator.
 14. The arcwelding torch of claim 13, wherein the insulator is a silicone basedthermoset plastic insulator.
 15. The arc welding torch of claim 11,further comprising an outer sleeve fit over the insulator, wherein theinsulator couples the outer sleeve to the gas diffuser.
 16. The arcwelding torch of claim 15, wherein the outer sleeve comprises a taperedshoulder configured to mate with a complementary taper of the nozzle,wherein a width of the shoulder determines a position of the nozzle withrespect to the contact tip.
 17. A method of modifying a position of acontact tip relative to a nozzle, the method comprising the steps of:providing a welding torch having a longitudinal axis, wherein thewelding torch comprises: a nozzle having a front end and a rear end, afirst gas diffuser assembly coupled to the nozzle, wherein the first gasdiffuser assembly comprises a first shoulder that abuts the rear end ofthe nozzle, thereby preventing the nozzle from moving axially beyond theshoulder, wherein the first shoulder has a first axial length, and acontact tip coupled to the first gas diffuser assembly, wherein a frontend of the contact tip is spaced from the front end of the nozzle by afirst distance; and replacing the first gas diffuser assembly with asecond gas diffuser assembly, wherein the second gas diffuser assemblycomprises a second shoulder having a second axial length that isdifferent from the first axial length, and wherein the front end of thecontact tip is spaced from the front end of the nozzle by a seconddistance that is different from the first distance.
 18. The method ofclaim 17, wherein the difference between the first distance and thesecond distance is equal to the difference between the first axiallength and the second axial length.
 19. The method of claim 17, whereinthe contact tip is retained entirely within the nozzle when the contacttip is coupled to the first gas diffuser, and wherein the contact tip isnot retained entirely within the nozzle when the contact tip is coupledto the second gas diffuser.
 20. The method of claim 17, wherein thecontact tip is retained entirely within the nozzle when the contact tipis coupled to the second gas diffuser, and wherein the contact tip isnot retained entirely within the nozzle when the contact tip is coupledto the first gas diffuser.